1. Field of the Invention
The present invention relates to a control apparatus for an optical apparatus such as a zoom lens.
2. Description of the Related Art
FIG. 12 shows a configuration of a conventional TV camera zoom lens. In the conventional TV camera zoom lens, when a command signal is inputted from an unillustrated lens controller, a CPU 103 as a controller outputs a control signal in response to the command signal, and this control signal is converted to an analog signal by a D/A converter 107 for inputting into a motor driving circuit 106. Thereby, a motor 105 is driven, and the position and speed of the movable lens unit 101 as an optical adjustment unit are controlled.
The position and speed of the movable lens unit 101 are detected by the CPU 103 via a potentiometer 102 and an A/D converter 104, and feedback control of the position and speed of the movable lens unit 101 is carried out.
In addition, in terms of a zoom lens which is often used while being carried with a camera on a shoulder for news coverage, etc., optical adjustment units such as a zoom unit, a focus unit, and an iris unit are often manually operated by rotating operation rings for operating those directly by hand, therefore, operation sensitivity of the operation rings is also regarded as important.
And, in order to avoid deterioration in the operation sensitivity of such operation rings and operation accuracy of the electrically controlled optical adjusting means as a result of a change over time, the zoom lens requires periodical maintenance such as cleaning, grease up, and optical adjustment.
Here, the frequency of use and time of use of zoom lenses are different depending on the users, and every zoom lens has a different lens condition for a fixed period after purchase. In addition, even when the same user uses a plurality of zoom lenses, ordinarily, the respective lenses are in different conditions.
However, in conventional zoom lenses, since there is no method for checking the history of use (operation history) such as the time and frequency of use, usage conditions, etc., maintenance is performed for all zoom lenses every fixed period of time uniformly. Namely, waste occurs in performing maintenance when in fact maintenance may not be required.